- Arm II: Patients receive p53 peptide vaccine IV over 5 minutes on day 1. Treatment in both arms repeats every 3 weeks for a total of 4 vaccinations (4 courses). During courses 3 and 4, patients also receive low-dose interleukin-2 (IL-2) SC daily on days 3-7 and days 10-14. Patients with stable or responding disease may continue to receive vaccine and IL-2 treatment for up to 2 years.